The present invention relates to baseball and softball bats. More particularly, the present invention relates to a composite bat having a metal sleeve.
Baseball and softball are very popular sports in the United States, Mexico, Cuba, Japan and elsewhere. Due to the competitive nature of the sports, players are constantly seeking ways of improving their performance. An important aspect of baseball and softball is the ability to effectively hit the ball. Aluminum (metal) bats are allowed in baseball amateur play from Little League to College levels. Metal bats are also typically used in slow and fast pitch softball. Such bats are advantageous over wood bats in that they do not break and splinter like wood bats and thus can be repeatedly used with consequent cost savings. Metal bats also have a larger optimal hitting area or power zone (commonly referred to as the “sweet spot”) than wood bats. Furthermore, the ball comes off a metal bat faster than a wood bat resulting in longer hits.
However, metal bats have certain disadvantages. Metal bats vibrate upon impact and may send painful vibrations into the hands and arms of the batter if the ball is not hit within the power zone of the bat. Metal bats, particularly aluminum bats, may also dent or otherwise deform due to forceful impacts with the ball. Metal bats also emit an undesirable high-pitched metallic sound, as opposed to the traditional sound heard when a wood bat contacts the ball.
Various attempts have been made to overcome the problems associated with metal bats. Some attempts have been to coat or wrap the exterior of the metal bat with materials such as carbon reinforcing fibers to enhance batting performance. These externally wrapped bats have been found to be aesthetically unpleasant and lacking in significant improvement. Other attempts have been made to insert internal layers or compartments within the metal bat to improve performance. Bats have been devised that incorporate both metal and composite materials. Such designs include utilizing multiple-layered graphite inserts to provide durability and flexibility to the bat, tubular coiled spring steel inserts to improve the spring-board effect when the ball contacts the bat, and pressurized air chambers within the bat. Bats that incorporate composite materials tend to be much lighter than metal bats. While providing benefits, these designs also have drawbacks. Some designs are very expensive to manufacture and are prone to structural failure. The composite sheaths break down over time, the bats are subject to premature longitudinal cracks in the barrel of the bat and damage is created at an interface of the metal and composite materials due to differences in the impact absorption and resistance characteristics of the materials.
Accordingly, there is a need for a bat which enhances the performance of the bat and overcomes the disadvantages previously experienced with metal bats. The present invention fulfills these needs and provides other related advantages.